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<a href="net__flow_2error_2error_8hpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="comment">/* Flow</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="comment"> * Copyright 2023 Akamai Technologies, Inc.</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment"> *</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="comment"> * Licensed under the Apache License, Version 2.0 (the</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="comment"> * &quot;License&quot;); you may not use this file except in</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="comment"> * compliance with the License.  You may obtain a copy</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="comment"> * of the License at</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span><span class="comment"> *</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="comment"> *   https://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span><span class="comment"> *</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span><span class="comment"> * Unless required by applicable law or agreed to in</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span><span class="comment"> * writing, software distributed under the License is</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span><span class="comment"> * distributed on an &quot;AS IS&quot; BASIS, WITHOUT WARRANTIES OR</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span><span class="comment"> * CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span><span class="comment"> * See the License for the specific language governing</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span><span class="comment"> * permissions and limitations under the License. */</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span><span class="comment"></span> </div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span><span class="comment">/// @file</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span><span class="comment"></span><span class="preprocessor">#pragma once</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span> </div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span><span class="preprocessor">#include &quot;<a class="code" href="common_8hpp.html">flow/common.hpp</a>&quot;</span></div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span><span class="comment"></span> </div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno">   23</span><span class="comment">/**</span></div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span><span class="comment"> * Namespace containing the net_flow module&#39;s extension of boost.system error conventions, so that Flow network</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="comment"> * protocol API can return codes/messages from within its own new set of error codes/messages.</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="comment"> *</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span><span class="comment"> * ### Synopsis ###</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="comment"> *</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span><span class="comment"> *   ~~~</span></div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span><span class="comment"> *   // Assign a code from net_flow&#39;s custom error code set -- to a *general* Error_code.</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span><span class="comment"> *   flow::Error_code code = flow::net_flow::error::Code::S_CONN_REFUSED;</span></div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span><span class="comment"> *   // code contains the int equivalent of S_CONN_REFUSED enum value; and a category pointer for your new</span></div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span><span class="comment"> *   // new code set to which S_CONN_REFUSED belonds.  So it&#39;s about the size of errno plus a pointer.</span></div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span><span class="comment"> *</span></div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span><span class="comment"> *   // Yet we have nice OO access to the equivalents of `errno` and `strerror(errno)`:</span></div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span><span class="comment"> *   std::cout &lt;&lt; &quot;General error value = [&quot; &lt;&lt; code.value() &lt;&lt; &quot;]; msg = [&quot; &lt;&lt; code.message() &lt;&lt; &quot;].\n&quot;;</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span><span class="comment"> *   // And we can throw an std::exception (`catch{}` can log the exception&#39;s .what() which will contain</span></div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno">   38</span><span class="comment"> *   // the numeric value, the human message, and the optional context string).</span></div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span><span class="comment"> *   throw flow::error::Runtime_error(code, &quot;Additional context info here!&quot;);</span></div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span><span class="comment"> *   ~~~</span></div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span><span class="comment"> *</span></div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span><span class="comment"> * ### Discussion ###</span></div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span><span class="comment"> * The contents of this `namespace` is one instance (and model example) for how one</span></div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span><span class="comment"> * can easily create their own simple error code set `enum` (and corresponding string messages) and hook it into</span></div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span><span class="comment"> * the flexible, yet maximally fast, boost.system error facility.  Another example (a peer of ours) would be</span></div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span><span class="comment"> * boost.asio&#39;s error code set.  See flow::Error_code doc header for a top-down summary of the</span></div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span><span class="comment"> * Flow-used-and-recommended error reporting system.</span></div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span><span class="comment"> *</span></div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span><span class="comment"> * For boost.system experts wondering whether there is support for `error_condition` equivalence (i.e., the</span></div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span><span class="comment"> * ability to compare a given `flow::error::error_code` to a more general `boost::system::error_condition`),</span></div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span><span class="comment"> * currently the answer is no, there isn&#39;t.  We may add `error_condition`s as #Error_code usage patterns emerge</span></div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span><span class="comment"> * over time.</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span><span class="comment"> *</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span><span class="comment"> * @internal</span></div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span><span class="comment"> *</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span><span class="comment"> * ### Summary of implementation ###</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span><span class="comment"> * This summarizes how we got the Synopsis above to work.  Replicate this in other modules as desired.</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span><span class="comment"> *   -# Define new code set `enum` in your own namespace (recommend `error` sub-namespace of your module) in</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span><span class="comment"> *      a new header file (recommend name based on namespace name).  Say we call it E.hpp.</span></div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span><span class="comment"> *   -# Also in E.hpp: Declare `make_error_code()` prototype right next to it.</span></div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span><span class="comment"> *   -# Also in E.hpp: Define `is_error_code_enum&lt;&gt;` specialization in `boost::system` namespace.</span></div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span><span class="comment"> *   -# In E.cpp: Define a new, non-public, category class C,</span></div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span><span class="comment"> *      whose main part is a simple function mapping each `enum` value to its human message (`switch()`).</span></div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span><span class="comment"> *      Instantiate a single `static` instance of C, perhaps as a member: `C::S_C`.</span></div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span><span class="comment"> *   -# Also in E.cpp: Implement the tiny boiler-plate `make_error_code()` from step 2.</span></div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span><span class="comment"> *      It constructs a general `Error_code` with the `int` version of the custom-`enum`</span></div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span><span class="comment"> *      value passed to it; and with a reference to `C::S_C` from previous step, thus identifying both the</span></div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span><span class="comment"> *      code set and the individual code.</span></div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span><span class="comment"> *</span></div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span><span class="comment"> * Result: One can directly assign codes from your new `enum` to the general `Error_code`</span></div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span><span class="comment"> * (a/k/a `boost::system::error_code`); see Synopsis above.</span></div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span><span class="comment"> *</span></div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span><span class="comment"> * ### Implementation discussion ###</span></div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span><span class="comment"> * While *using* this error reporting system is simple and convenient, the internal implementation is</span></div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span><span class="comment"> * (IMO) cryptic albeit fairly concise.  I followed the guide:</span></div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span><span class="comment"> *</span></div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span><span class="comment"> *   http://blog.think-async.com/2010/04/system-error-support-in-c0x-part-4.html</span></div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span><span class="comment"> *</span></div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span><span class="comment"> * Note that this isn&#39;t some random web page but rather a detailed a walkthrough by the author of</span></div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span><span class="comment"> * boost.system (which includes `error_code`) itself.  In addition, its author wrote boost.asio, which we use</span></div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span><span class="comment"> * extensively in this implementation.  Finally, boost.asio&#39;s own extension of the `error_code`/etc. system --</span></div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span><span class="comment"> * for its own error reporting, which is API-wise quite similar to this one -- can be seen (in boost.asio&#39;s</span></div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span><span class="comment"> * largely headers-only implementation) to follow the above guide ~99% to the letter.</span></div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span><span class="comment"> *</span></div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span><span class="comment"> * What&#39;s rather odd is that boost.system&#39;s actual formal documentation, e.g.,</span></div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span><span class="comment"> *</span></div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span><span class="comment"> *   http://www.boost.org/doc/libs/1_50_0/libs/system/doc/index.html,</span></div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno">   88</span><span class="comment"> *</span></div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span><span class="comment"> * does not in any way explain how to implement all this properly.  The above guide is not included in that</span></div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span><span class="comment"> * official doc, nor is it linked.  In fact, following the formal documentation without a supernatural (IMO)</span></div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno">   91</span><span class="comment"> * level of understanding of the author&#39;s intentions, would likely lead to the wrong implementation.</span></div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span><span class="comment"> * Most visibly, for example, the docs say that `error_code` is for platform-dependent error codes; while</span></div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span><span class="comment"> * `error_condition` is for portable error codes, or something very, very close to that.</span></div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span><span class="comment"> * Well (I thought originally), Flow&#39;s errors ARE platform-independent, so I guess I should use</span></div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span><span class="comment"> * `error_condition`s then!  So originally, all the Flow APIs that reported errors took `Error_condition*`</span></div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span><span class="comment"> * arguments, not `Error_code*` arguments.  Only after some colleagues remarked that this appears wrong,</span></div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span><span class="comment"> * and pointed out the above guide, did I realize that I did that wrong and switched to `Error_code`.</span></div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span><span class="comment"> * In particular, the guide elucidates: `error_code` is to report a &quot;low-level&quot; or &quot;system-level&quot; specific</span></div>
<div class="line"><a id="l00099" name="l00099"></a><span class="lineno">   99</span><span class="comment"> * error (not necessarily computer platform-dependent, as the formal doc might seem to say), while</span></div>
<div class="line"><a id="l00100" name="l00100"></a><span class="lineno">  100</span><span class="comment"> * `error_condition` is something to (optionally) &quot;check against&quot; as a higher-level or more abstract piece</span></div>
<div class="line"><a id="l00101" name="l00101"></a><span class="lineno">  101</span><span class="comment"> * of error handling logic.  So in fact any original error should be an `error_code`, and `error_condition`</span></div>
<div class="line"><a id="l00102" name="l00102"></a><span class="lineno">  102</span><span class="comment"> * is an _optional_ layer one _might_ add to help working with `error_code`s.</span></div>
<div class="line"><a id="l00103" name="l00103"></a><span class="lineno">  103</span><span class="comment"> */</span></div>
<div class="line"><a id="l00104" name="l00104"></a><span class="lineno">  104</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceflow_1_1net__flow_1_1error.html">flow::net_flow::error</a></div>
<div class="line"><a id="l00105" name="l00105"></a><span class="lineno">  105</span>{</div>
<div class="line"><a id="l00106" name="l00106"></a><span class="lineno">  106</span> </div>
<div class="line"><a id="l00107" name="l00107"></a><span class="lineno">  107</span><span class="comment">// Types.</span></div>
<div class="line"><a id="l00108" name="l00108"></a><span class="lineno">  108</span><span class="comment"></span> </div>
<div class="line"><a id="l00109" name="l00109"></a><span class="lineno">  109</span><span class="comment">/**</span></div>
<div class="line"><a id="l00110" name="l00110"></a><span class="lineno">  110</span><span class="comment"> * All possible errors returned (via flow::Error_code arguments) by flow::net_flow functions/methods.</span></div>
<div class="line"><a id="l00111" name="l00111"></a><span class="lineno">  111</span><span class="comment"> * These values are convertible to flow::Error_code (a/k/a `boost::system::error_code`) and thus</span></div>
<div class="line"><a id="l00112" name="l00112"></a><span class="lineno">  112</span><span class="comment"> * extend the set of errors that flow::Error_code can represent.</span></div>
<div class="line"><a id="l00113" name="l00113"></a><span class="lineno">  113</span><span class="comment"> *</span></div>
<div class="line"><a id="l00114" name="l00114"></a><span class="lineno">  114</span><span class="comment"> * @internal</span></div>
<div class="line"><a id="l00115" name="l00115"></a><span class="lineno">  115</span><span class="comment"> *</span></div>
<div class="line"><a id="l00116" name="l00116"></a><span class="lineno">  116</span><span class="comment"> * When you add a value to this `enum`, also add its description to</span></div>
<div class="line"><a id="l00117" name="l00117"></a><span class="lineno">  117</span><span class="comment"> * net_flow_error.cpp’s Category::message().  This description must be identical to the description</span></div>
<div class="line"><a id="l00118" name="l00118"></a><span class="lineno">  118</span><span class="comment"> * in the /// comment below, or at least as close as possible.</span></div>
<div class="line"><a id="l00119" name="l00119"></a><span class="lineno">  119</span><span class="comment"> *</span></div>
<div class="line"><a id="l00120" name="l00120"></a><span class="lineno">  120</span><span class="comment"> * If, when adding a new revision of the code, you add a value to this `enum`, add it to the end.</span></div>
<div class="line"><a id="l00121" name="l00121"></a><span class="lineno">  121</span><span class="comment"> * If, when adding a new revision of the code, you deprecate a value in this `enum`, do not delete</span></div>
<div class="line"><a id="l00122" name="l00122"></a><span class="lineno">  122</span><span class="comment"> * it from this `enum`.  Instead mark it as deprecated here and then remove it from</span></div>
<div class="line"><a id="l00123" name="l00123"></a><span class="lineno">  123</span><span class="comment"> * Flow_category::message().</span></div>
<div class="line"><a id="l00124" name="l00124"></a><span class="lineno">  124</span><span class="comment"> *</span></div>
<div class="line"><a id="l00125" name="l00125"></a><span class="lineno">  125</span><span class="comment"> * Errors that indicate apparent logic bugs (in other words, assertions that we were too afraid</span></div>
<div class="line"><a id="l00126" name="l00126"></a><span class="lineno">  126</span><span class="comment"> * to write as actual `assert()`s) should be prefixed with `S_INTERNAL_ERROR_`, and their messages</span></div>
<div class="line"><a id="l00127" name="l00127"></a><span class="lineno">  127</span><span class="comment"> * should also indicate &quot;Internal error: &quot;.</span></div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span><span class="comment"> *</span></div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span><span class="comment"> * @todo Consider adding specific subclasses of flow::error::Runtime_error</span></div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span><span class="comment"> * for the key codes, like `WAIT_INTERRUPTED` and `USER_TIMEOUT`.</span></div>
<div class="line"><a id="l00131" name="l00131"></a><span class="lineno">  131</span><span class="comment"> * In doing so, make sure there&#39;s an automated syntactic-sugary way of doing this, so that one need only add</span></div>
<div class="line"><a id="l00132" name="l00132"></a><span class="lineno">  132</span><span class="comment"> * a code&lt;-&gt;class pair into some internal centralized mapping, automatically making system emit the proper</span></div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span><span class="comment"> * exception class, defaulting to plain Runtime_error if not specially-mapped.</span></div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span><span class="comment"> */</span></div>
<div class="line"><a id="l00135" name="l00135"></a><span class="lineno"><a class="line" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482">  135</a></span><span class="keyword">enum class</span> <a class="code hl_enumeration" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482">Code</a></div>
<div class="line"><a id="l00136" name="l00136"></a><span class="lineno">  136</span>{<span class="comment"></span></div>
<div class="line"><a id="l00137" name="l00137"></a><span class="lineno">  137</span><span class="comment">  /// Node not running.</span></div>
<div class="line"><a id="l00138" name="l00138"></a><span class="lineno">  138</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482affac5d80b4e72f2e55bbbfadce2efd2e">S_NODE_NOT_RUNNING</a> = 1,<span class="comment"></span></div>
<div class="line"><a id="l00139" name="l00139"></a><span class="lineno">  139</span><span class="comment">  /// Cannot ask to connect to &quot;any&quot; IP address.  Use specific IP address.</span></div>
<div class="line"><a id="l00140" name="l00140"></a><span class="lineno">  140</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482aac3ec8d83192e9cd271376fce4001e99">S_CANNOT_CONNECT_TO_IP_ANY</a>,<span class="comment"></span></div>
<div class="line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span><span class="comment">  /// Flow port number is not in the valid service port number range.</span></div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482abb79e941df00b67a8631a9361ee5a4d1">S_INVALID_SERVICE_PORT_NUMBER</a>,<span class="comment"></span></div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span><span class="comment">  /// Flow port already reserved.</span></div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a2c42b01b60ebe4834e9be3933ce94cb6">S_PORT_TAKEN</a>,<span class="comment"></span></div>
<div class="line"><a id="l00145" name="l00145"></a><span class="lineno">  145</span><span class="comment">  /**</span></div>
<div class="line"><a id="l00146" name="l00146"></a><span class="lineno">  146</span><span class="comment">   * Internal error:  Tried to return Flow port which had not been reserved.</span></div>
<div class="line"><a id="l00147" name="l00147"></a><span class="lineno">  147</span><span class="comment">   *</span></div>
<div class="line"><a id="l00148" name="l00148"></a><span class="lineno">  148</span><span class="comment">   * @internal</span></div>
<div class="line"><a id="l00149" name="l00149"></a><span class="lineno">  149</span><span class="comment">   *</span></div>
<div class="line"><a id="l00150" name="l00150"></a><span class="lineno">  150</span><span class="comment">   * @note By its definition (see above brief description), it can only be triggered by Port_space::return_port().</span></div>
<div class="line"><a id="l00151" name="l00151"></a><span class="lineno">  151</span><span class="comment">   *       If one looks at all the calls to said method in practice, they&#39;ll note</span></div>
<div class="line"><a id="l00152" name="l00152"></a><span class="lineno">  152</span><span class="comment">   *       that it returning a truthy `*err_code` of any kind is unexpected to the point where it is an</span></div>
<div class="line"><a id="l00153" name="l00153"></a><span class="lineno">  153</span><span class="comment">   *       `assert()` failure, as least as of this writing.  Therefore, `S_..._PORT_NOT_TAKEN` is indeed deserving of</span></div>
<div class="line"><a id="l00154" name="l00154"></a><span class="lineno">  154</span><span class="comment">   *       having the `INTERNAL_ERROR` prefix (meaning, it occurring implies a programming error inside library).</span></div>
<div class="line"><a id="l00155" name="l00155"></a><span class="lineno">  155</span><span class="comment">   *       As of this writing, unless `assert()`s are compiled out, it&#39;s not even possible for the error to get to</span></div>
<div class="line"><a id="l00156" name="l00156"></a><span class="lineno">  156</span><span class="comment">   *       the user (but that may change by removing some or all of those `assert()`s -- in which case the error&#39;s</span></div>
<div class="line"><a id="l00157" name="l00157"></a><span class="lineno">  157</span><span class="comment">   *       naming matters more.  Bottom line, it is an `..._INTERNAL_ERROR_...` until some condition in practice</span></div>
<div class="line"><a id="l00158" name="l00158"></a><span class="lineno">  158</span><span class="comment">   *       makes it possible that Port_space::return_port() failing that way is not a result of a programming error.</span></div>
<div class="line"><a id="l00159" name="l00159"></a><span class="lineno">  159</span><span class="comment">   */</span></div>
<div class="line"><a id="l00160" name="l00160"></a><span class="lineno">  160</span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a0eac39cc62ef841927a2f69a3c04db4e">S_INTERNAL_ERROR_PORT_NOT_TAKEN</a>,<span class="comment"></span></div>
<div class="line"><a id="l00161" name="l00161"></a><span class="lineno">  161</span><span class="comment">  /// No more ephemeral Flow ports available.</span></div>
<div class="line"><a id="l00162" name="l00162"></a><span class="lineno">  162</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a1975df7ed76c42660cbdc6039d5c70c5">S_OUT_OF_PORTS</a>,<span class="comment"></span></div>
<div class="line"><a id="l00163" name="l00163"></a><span class="lineno">  163</span><span class="comment">  /// Internal error:  Ephemeral port double reservation allowed.</span></div>
<div class="line"><a id="l00164" name="l00164"></a><span class="lineno">  164</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ae90ff1c87f2393dd6b14232b159f02b2">S_INTERNAL_ERROR_PORT_COLLISION</a>,<span class="comment"></span></div>
<div class="line"><a id="l00165" name="l00165"></a><span class="lineno">  165</span><span class="comment">  /// Connection reset because of unexpected/illegal behavior by the other side.</span></div>
<div class="line"><a id="l00166" name="l00166"></a><span class="lineno">  166</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab2c97d0fbc585d3726ec79c7802da891">S_CONN_RESET_BAD_PEER_BEHAVIOR</a>,<span class="comment"></span></div>
<div class="line"><a id="l00167" name="l00167"></a><span class="lineno">  167</span><span class="comment">  /// Other side refused connection.</span></div>
<div class="line"><a id="l00168" name="l00168"></a><span class="lineno">  168</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482aa220d89e1d0e34bab02ed2fc7512be9b">S_CONN_REFUSED</a>,<span class="comment"></span></div>
<div class="line"><a id="l00169" name="l00169"></a><span class="lineno">  169</span><span class="comment">  /// Other side did not complete connection handshake within the allowed time; perhaps no one is listening.</span></div>
<div class="line"><a id="l00170" name="l00170"></a><span class="lineno">  170</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a074451c0bc9f5ae37e0c8fbe82677090">S_CONN_TIMEOUT</a>,<span class="comment"></span></div>
<div class="line"><a id="l00171" name="l00171"></a><span class="lineno">  171</span><span class="comment">  /// Other side reset an established connection.</span></div>
<div class="line"><a id="l00172" name="l00172"></a><span class="lineno">  172</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a138a08bb4d41be4cdbc6311a1a617cf4">S_CONN_RESET_BY_OTHER_SIDE</a>,<span class="comment"></span></div>
<div class="line"><a id="l00173" name="l00173"></a><span class="lineno">  173</span><span class="comment">  /// Connection reset because a packet has been retransmitted too many times.</span></div>
<div class="line"><a id="l00174" name="l00174"></a><span class="lineno">  174</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3c1dc923491f5e20763fc27d025665d4">S_CONN_RESET_TOO_MANY_REXMITS</a>,<span class="comment"></span></div>
<div class="line"><a id="l00175" name="l00175"></a><span class="lineno">  175</span><span class="comment">  /// Other side has sent packets with inconsistent sequence numbers.</span></div>
<div class="line"><a id="l00176" name="l00176"></a><span class="lineno">  176</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a8ad7147a3e4e63313c7a5954790cd458">S_SEQ_NUM_ARITHMETIC_FAILURE</a>,<span class="comment"></span></div>
<div class="line"><a id="l00177" name="l00177"></a><span class="lineno">  177</span><span class="comment">  /// Other side has sent packet with sequence number that implies a port collision between two connections over time.</span></div>
<div class="line"><a id="l00178" name="l00178"></a><span class="lineno">  178</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a891201a96c5838bbb24cc9ed08b47765">S_SEQ_NUM_IMPLIES_CONNECTION_COLLISION</a>,<span class="comment"></span></div>
<div class="line"><a id="l00179" name="l00179"></a><span class="lineno">  179</span><span class="comment">  /// Node shutting down.</span></div>
<div class="line"><a id="l00180" name="l00180"></a><span class="lineno">  180</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5d57c6a6029d7c6a9e5442ac72ac7a6b">S_NODE_SHUTTING_DOWN</a>,<span class="comment"></span></div>
<div class="line"><a id="l00181" name="l00181"></a><span class="lineno">  181</span><span class="comment">  /// User code on this side abruptly closed connection; other side may be informed of this.</span></div>
<div class="line"><a id="l00182" name="l00182"></a><span class="lineno">  182</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a35606f4143e15dbe6bc03a543599dec8">S_USER_CLOSED_ABRUPTLY</a>,<span class="comment"></span></div>
<div class="line"><a id="l00183" name="l00183"></a><span class="lineno">  183</span><span class="comment">  /// Attempted operation on an event set, when that event set was closed.</span></div>
<div class="line"><a id="l00184" name="l00184"></a><span class="lineno">  184</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ae643fd244bd1d6b483295cb9f356b0ae">S_EVENT_SET_CLOSED</a>,<span class="comment"></span></div>
<div class="line"><a id="l00185" name="l00185"></a><span class="lineno">  185</span><span class="comment">  /// Attempted to write to an event set, while a wait operation was pending on that event set.</span></div>
<div class="line"><a id="l00186" name="l00186"></a><span class="lineno">  186</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3f2c29ade2454001982c033a37fd9c79">S_EVENT_SET_IMMUTABLE_WHEN_WAITING</a>,<span class="comment"></span></div>
<div class="line"><a id="l00187" name="l00187"></a><span class="lineno">  187</span><span class="comment">  /// Attempted to add an event into an event set, but that event already exists.</span></div>
<div class="line"><a id="l00188" name="l00188"></a><span class="lineno">  188</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a8f3a13ffefc4897da606c86e60a4422f">S_EVENT_SET_EVENT_ALREADY_EXISTS</a>,<span class="comment"></span></div>
<div class="line"><a id="l00189" name="l00189"></a><span class="lineno">  189</span><span class="comment">  /// Attempted to work with an event that does not exist in the event set.</span></div>
<div class="line"><a id="l00190" name="l00190"></a><span class="lineno">  190</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a96f464959b6ce918048a2167c23f1c0b">S_EVENT_SET_EVENT_DOES_NOT_EXIST</a>,<span class="comment"></span></div>
<div class="line"><a id="l00191" name="l00191"></a><span class="lineno">  191</span><span class="comment">  /// Attempted to wait on or poll an event set while already waiting on that event set.</span></div>
<div class="line"><a id="l00192" name="l00192"></a><span class="lineno">  192</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482adccb025a96014a74a1435481ec2b58ac">S_EVENT_SET_DOUBLE_WAIT_OR_POLL</a>,<span class="comment"></span></div>
<div class="line"><a id="l00193" name="l00193"></a><span class="lineno">  193</span><span class="comment">  /// Attempted to wait on an event set without specifying event on which to wait.</span></div>
<div class="line"><a id="l00194" name="l00194"></a><span class="lineno">  194</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5cbb0762dc20632c76db479f40237492">S_EVENT_SET_NO_EVENTS</a>,<span class="comment"></span></div>
<div class="line"><a id="l00195" name="l00195"></a><span class="lineno">  195</span><span class="comment">  /// Attempted to check wait results while still waiting.</span></div>
<div class="line"><a id="l00196" name="l00196"></a><span class="lineno">  196</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3e273da0f7d2f231dbfaab8d07fd5ecd">S_EVENT_SET_RESULT_CHECK_WHEN_WAITING</a>,<span class="comment"></span></div>
<div class="line"><a id="l00197" name="l00197"></a><span class="lineno">  197</span><span class="comment">  /// During connection user supplied metadata that is too large.</span></div>
<div class="line"><a id="l00198" name="l00198"></a><span class="lineno">  198</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a9a2cbc62120ca52c1f7e695b56b2bdcd">S_CONN_METADATA_TOO_LARGE</a>,<span class="comment"></span></div>
<div class="line"><a id="l00199" name="l00199"></a><span class="lineno">  199</span><span class="comment">  /// When setting options, tried to set an unchangeable (static) option.</span></div>
<div class="line"><a id="l00200" name="l00200"></a><span class="lineno">  200</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ad7b8da59bb61205572fe985c29863e58">S_STATIC_OPTION_CHANGED</a>,<span class="comment"></span></div>
<div class="line"><a id="l00201" name="l00201"></a><span class="lineno">  201</span><span class="comment">  /// When setting options, at least one option&#39;s value violates a required condition on that option.</span></div>
<div class="line"><a id="l00202" name="l00202"></a><span class="lineno">  202</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5e0c2b54a5427bc09ecf0dee603ce450">S_OPTION_CHECK_FAILED</a>,<span class="comment"></span></div>
<div class="line"><a id="l00203" name="l00203"></a><span class="lineno">  203</span><span class="comment">  /// A blocking (`sync_`) or background-blocking (`async_`) operation was interrupted, such as by a signal.</span></div>
<div class="line"><a id="l00204" name="l00204"></a><span class="lineno">  204</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab92ec3b2b78d74acf0fda0786f601df5">S_WAIT_INTERRUPTED</a>,<span class="comment"></span></div>
<div class="line"><a id="l00205" name="l00205"></a><span class="lineno">  205</span><span class="comment">  /// A blocking (`sync_`) or background-blocking (`async_`) operation timed out versus user-supplied time limit.</span></div>
<div class="line"><a id="l00206" name="l00206"></a><span class="lineno">  206</span><span class="comment"></span>  <a class="code hl_enumvalue" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab835895723a7d71c964b84e0f0b78c3c">S_WAIT_USER_TIMEOUT</a></div>
<div class="line"><a id="l00207" name="l00207"></a><span class="lineno">  207</span>}; <span class="comment">// enum class Code</span></div>
<div class="line"><a id="l00208" name="l00208"></a><span class="lineno">  208</span> </div>
<div class="line"><a id="l00209" name="l00209"></a><span class="lineno">  209</span><span class="comment">// Functions.</span></div>
<div class="line"><a id="l00210" name="l00210"></a><span class="lineno">  210</span><span class="comment"></span> </div>
<div class="line"><a id="l00211" name="l00211"></a><span class="lineno">  211</span><span class="comment">/**</span></div>
<div class="line"><a id="l00212" name="l00212"></a><span class="lineno">  212</span><span class="comment"> * Given a `Code` `enum` value, creates a lightweight flow::Error_code (a/k/a boost.system `error_code`)</span></div>
<div class="line"><a id="l00213" name="l00213"></a><span class="lineno">  213</span><span class="comment"> * representing that error.  This is needed to make the</span></div>
<div class="line"><a id="l00214" name="l00214"></a><span class="lineno">  214</span><span class="comment"> * `boost::system::error_code::error_code&lt;Code&gt;()` template implementation work.  Or, slightly more in English,</span></div>
<div class="line"><a id="l00215" name="l00215"></a><span class="lineno">  215</span><span class="comment"> * it glues the (completely general) flow::Error_code to the (net_flow-specific) error code set</span></div>
<div class="line"><a id="l00216" name="l00216"></a><span class="lineno">  216</span><span class="comment"> * flow::net_flow::error::Code, so that one can implicitly covert from the latter to the former.</span></div>
<div class="line"><a id="l00217" name="l00217"></a><span class="lineno">  217</span><span class="comment"> *</span></div>
<div class="line"><a id="l00218" name="l00218"></a><span class="lineno">  218</span><span class="comment"> * @param err_code</span></div>
<div class="line"><a id="l00219" name="l00219"></a><span class="lineno">  219</span><span class="comment"> *        The `enum` value.</span></div>
<div class="line"><a id="l00220" name="l00220"></a><span class="lineno">  220</span><span class="comment"> * @return A corresponding flow::Error_code.</span></div>
<div class="line"><a id="l00221" name="l00221"></a><span class="lineno">  221</span><span class="comment"> */</span></div>
<div class="line"><a id="l00222" name="l00222"></a><span class="lineno">  222</span><a class="code hl_typedef" href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">Error_code</a> <a class="code hl_function" href="namespaceflow_1_1net__flow_1_1error.html#a6d35c37eb70a494bb27aa807c41de176">make_error_code</a>(<a class="code hl_enumeration" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482">Code</a> err_code);</div>
<div class="line"><a id="l00223" name="l00223"></a><span class="lineno">  223</span> </div>
<div class="line"><a id="l00224" name="l00224"></a><span class="lineno">  224</span>} <span class="comment">// namespace flow::net_flow::error</span></div>
<div class="line"><a id="l00225" name="l00225"></a><span class="lineno">  225</span><span class="comment"></span> </div>
<div class="line"><a id="l00226" name="l00226"></a><span class="lineno">  226</span><span class="comment">/// We may add some ADL-based overloads into this namespace outside `flow`.</span></div>
<div class="line"><a id="l00227" name="l00227"></a><span class="lineno"><a class="line" href="namespaceboost_1_1system.html">  227</a></span><span class="comment"></span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceboost_1_1system.html">boost::system</a></div>
<div class="line"><a id="l00228" name="l00228"></a><span class="lineno">  228</span>{</div>
<div class="line"><a id="l00229" name="l00229"></a><span class="lineno">  229</span> </div>
<div class="line"><a id="l00230" name="l00230"></a><span class="lineno">  230</span><span class="comment">// Types.</span></div>
<div class="line"><a id="l00231" name="l00231"></a><span class="lineno">  231</span><span class="comment"></span> </div>
<div class="line"><a id="l00232" name="l00232"></a><span class="lineno">  232</span><span class="comment">/**</span></div>
<div class="line"><a id="l00233" name="l00233"></a><span class="lineno">  233</span><span class="comment"> * Ummm -- it specializes this `struct` to -- look -- the end result is boost.system uses this as</span></div>
<div class="line"><a id="l00234" name="l00234"></a><span class="lineno">  234</span><span class="comment"> * authorization to make `enum` `Code` convertible to `Error_code`.  The non-specialized</span></div>
<div class="line"><a id="l00235" name="l00235"></a><span class="lineno">  235</span><span class="comment"> * version of this sets &quot;value&quot; to false, so that random arbitary `enum`s can&#39;t just be used as</span></div>
<div class="line"><a id="l00236" name="l00236"></a><span class="lineno">  236</span><span class="comment"> * `Error_code`s.  Note that this is the offical way to accomplish that, as (confusingly but</span></div>
<div class="line"><a id="l00237" name="l00237"></a><span class="lineno">  237</span><span class="comment"> * formally) documented in boost.system docs.</span></div>
<div class="line"><a id="l00238" name="l00238"></a><span class="lineno">  238</span><span class="comment"> */</span></div>
<div class="line"><a id="l00239" name="l00239"></a><span class="lineno">  239</span><span class="keyword">template</span>&lt;&gt;</div>
<div class="line"><a id="l00240" name="l00240"></a><span class="lineno"><a class="line" href="structboost_1_1system_1_1is__error__code__enum_3_1_1flow_1_1net__flow_1_1error_1_1Code_01_4.html">  240</a></span><span class="keyword">struct </span>is_error_code_enum&lt;::<a class="code hl_enumeration" href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482">flow::net_flow::error::Code</a>&gt;</div>
<div class="line"><a id="l00241" name="l00241"></a><span class="lineno">  241</span>{<span class="comment"></span></div>
<div class="line"><a id="l00242" name="l00242"></a><span class="lineno">  242</span><span class="comment">  /// Means `Code` `enum` values can be used for flow::Error_code.</span></div>
<div class="line"><a id="l00243" name="l00243"></a><span class="lineno"><a class="line" href="structboost_1_1system_1_1is__error__code__enum_3_1_1flow_1_1net__flow_1_1error_1_1Code_01_4.html#a3a8d09a793eba817e718a3837fd1cd75">  243</a></span><span class="comment"></span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">bool</span> value = <span class="keyword">true</span>;</div>
<div class="line"><a id="l00244" name="l00244"></a><span class="lineno">  244</span>  <span class="comment">/* ^-- Could instead derive publicly from true_type, but then we&#39;d have to find a true_type</span></div>
<div class="line"><a id="l00245" name="l00245"></a><span class="lineno">  245</span><span class="comment">   * in some header we could use. At any rate this works just the same, and boost.asio does it this way, so if</span></div>
<div class="line"><a id="l00246" name="l00246"></a><span class="lineno">  246</span><span class="comment">   * it&#39;s good enough for them (the author of boost.asio = the author of boost.system [error_code, etc.]),</span></div>
<div class="line"><a id="l00247" name="l00247"></a><span class="lineno">  247</span><span class="comment">   * I say it&#39;s good enough for us. */</span></div>
<div class="line"><a id="l00248" name="l00248"></a><span class="lineno">  248</span>};</div>
<div class="line"><a id="l00249" name="l00249"></a><span class="lineno">  249</span> </div>
<div class="line"><a id="l00250" name="l00250"></a><span class="lineno">  250</span>} <span class="comment">// namespace boost::system</span></div>
<div class="ttc" id="acommon_8hpp_html"><div class="ttname"><a href="common_8hpp.html">common.hpp</a></div></div>
<div class="ttc" id="anamespaceboost_1_1system_html"><div class="ttname"><a href="namespaceboost_1_1system.html">boost::system</a></div><div class="ttdoc">We may add some ADL-based overloads into this namespace outside flow.</div><div class="ttdef"><b>Definition:</b> <a href="net__flow_2error_2error_8hpp_source.html#l00227">error.hpp:228</a></div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html">flow::net_flow::error</a></div><div class="ttdoc">Namespace containing the net_flow module's extension of boost.system error conventions,...</div><div class="ttdef"><b>Definition:</b> <a href="net__flow_2error_2error_8cpp_source.html#l00023">error.cpp:24</a></div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482">flow::net_flow::error::Code</a></div><div class="ttdeci">Code</div><div class="ttdoc">All possible errors returned (via flow::Error_code arguments) by flow::net_flow functions/methods.</div><div class="ttdef"><b>Definition:</b> <a href="net__flow_2error_2error_8hpp_source.html#l00135">error.hpp:136</a></div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a074451c0bc9f5ae37e0c8fbe82677090"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a074451c0bc9f5ae37e0c8fbe82677090">flow::net_flow::error::Code::S_CONN_TIMEOUT</a></div><div class="ttdeci">@ S_CONN_TIMEOUT</div><div class="ttdoc">Other side did not complete connection handshake within the allowed time; perhaps no one is listening...</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a0eac39cc62ef841927a2f69a3c04db4e"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a0eac39cc62ef841927a2f69a3c04db4e">flow::net_flow::error::Code::S_INTERNAL_ERROR_PORT_NOT_TAKEN</a></div><div class="ttdeci">@ S_INTERNAL_ERROR_PORT_NOT_TAKEN</div><div class="ttdoc">Internal error: Tried to return Flow port which had not been reserved.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a138a08bb4d41be4cdbc6311a1a617cf4"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a138a08bb4d41be4cdbc6311a1a617cf4">flow::net_flow::error::Code::S_CONN_RESET_BY_OTHER_SIDE</a></div><div class="ttdeci">@ S_CONN_RESET_BY_OTHER_SIDE</div><div class="ttdoc">Other side reset an established connection.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a1975df7ed76c42660cbdc6039d5c70c5"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a1975df7ed76c42660cbdc6039d5c70c5">flow::net_flow::error::Code::S_OUT_OF_PORTS</a></div><div class="ttdeci">@ S_OUT_OF_PORTS</div><div class="ttdoc">No more ephemeral Flow ports available.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a2c42b01b60ebe4834e9be3933ce94cb6"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a2c42b01b60ebe4834e9be3933ce94cb6">flow::net_flow::error::Code::S_PORT_TAKEN</a></div><div class="ttdeci">@ S_PORT_TAKEN</div><div class="ttdoc">Flow port already reserved.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a35606f4143e15dbe6bc03a543599dec8"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a35606f4143e15dbe6bc03a543599dec8">flow::net_flow::error::Code::S_USER_CLOSED_ABRUPTLY</a></div><div class="ttdeci">@ S_USER_CLOSED_ABRUPTLY</div><div class="ttdoc">User code on this side abruptly closed connection; other side may be informed of this.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a3c1dc923491f5e20763fc27d025665d4"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3c1dc923491f5e20763fc27d025665d4">flow::net_flow::error::Code::S_CONN_RESET_TOO_MANY_REXMITS</a></div><div class="ttdeci">@ S_CONN_RESET_TOO_MANY_REXMITS</div><div class="ttdoc">Connection reset because a packet has been retransmitted too many times.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a3e273da0f7d2f231dbfaab8d07fd5ecd"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3e273da0f7d2f231dbfaab8d07fd5ecd">flow::net_flow::error::Code::S_EVENT_SET_RESULT_CHECK_WHEN_WAITING</a></div><div class="ttdeci">@ S_EVENT_SET_RESULT_CHECK_WHEN_WAITING</div><div class="ttdoc">Attempted to check wait results while still waiting.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a3f2c29ade2454001982c033a37fd9c79"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a3f2c29ade2454001982c033a37fd9c79">flow::net_flow::error::Code::S_EVENT_SET_IMMUTABLE_WHEN_WAITING</a></div><div class="ttdeci">@ S_EVENT_SET_IMMUTABLE_WHEN_WAITING</div><div class="ttdoc">Attempted to write to an event set, while a wait operation was pending on that event set.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a5cbb0762dc20632c76db479f40237492"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5cbb0762dc20632c76db479f40237492">flow::net_flow::error::Code::S_EVENT_SET_NO_EVENTS</a></div><div class="ttdeci">@ S_EVENT_SET_NO_EVENTS</div><div class="ttdoc">Attempted to wait on an event set without specifying event on which to wait.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a5d57c6a6029d7c6a9e5442ac72ac7a6b"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5d57c6a6029d7c6a9e5442ac72ac7a6b">flow::net_flow::error::Code::S_NODE_SHUTTING_DOWN</a></div><div class="ttdeci">@ S_NODE_SHUTTING_DOWN</div><div class="ttdoc">Node shutting down.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a5e0c2b54a5427bc09ecf0dee603ce450"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a5e0c2b54a5427bc09ecf0dee603ce450">flow::net_flow::error::Code::S_OPTION_CHECK_FAILED</a></div><div class="ttdeci">@ S_OPTION_CHECK_FAILED</div><div class="ttdoc">When setting options, at least one option's value violates a required condition on that option.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a891201a96c5838bbb24cc9ed08b47765"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a891201a96c5838bbb24cc9ed08b47765">flow::net_flow::error::Code::S_SEQ_NUM_IMPLIES_CONNECTION_COLLISION</a></div><div class="ttdeci">@ S_SEQ_NUM_IMPLIES_CONNECTION_COLLISION</div><div class="ttdoc">Other side has sent packet with sequence number that implies a port collision between two connections...</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a8ad7147a3e4e63313c7a5954790cd458"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a8ad7147a3e4e63313c7a5954790cd458">flow::net_flow::error::Code::S_SEQ_NUM_ARITHMETIC_FAILURE</a></div><div class="ttdeci">@ S_SEQ_NUM_ARITHMETIC_FAILURE</div><div class="ttdoc">Other side has sent packets with inconsistent sequence numbers.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a8f3a13ffefc4897da606c86e60a4422f"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a8f3a13ffefc4897da606c86e60a4422f">flow::net_flow::error::Code::S_EVENT_SET_EVENT_ALREADY_EXISTS</a></div><div class="ttdeci">@ S_EVENT_SET_EVENT_ALREADY_EXISTS</div><div class="ttdoc">Attempted to add an event into an event set, but that event already exists.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a96f464959b6ce918048a2167c23f1c0b"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a96f464959b6ce918048a2167c23f1c0b">flow::net_flow::error::Code::S_EVENT_SET_EVENT_DOES_NOT_EXIST</a></div><div class="ttdeci">@ S_EVENT_SET_EVENT_DOES_NOT_EXIST</div><div class="ttdoc">Attempted to work with an event that does not exist in the event set.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482a9a2cbc62120ca52c1f7e695b56b2bdcd"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482a9a2cbc62120ca52c1f7e695b56b2bdcd">flow::net_flow::error::Code::S_CONN_METADATA_TOO_LARGE</a></div><div class="ttdeci">@ S_CONN_METADATA_TOO_LARGE</div><div class="ttdoc">During connection user supplied metadata that is too large.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482aa220d89e1d0e34bab02ed2fc7512be9b"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482aa220d89e1d0e34bab02ed2fc7512be9b">flow::net_flow::error::Code::S_CONN_REFUSED</a></div><div class="ttdeci">@ S_CONN_REFUSED</div><div class="ttdoc">Other side refused connection.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482aac3ec8d83192e9cd271376fce4001e99"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482aac3ec8d83192e9cd271376fce4001e99">flow::net_flow::error::Code::S_CANNOT_CONNECT_TO_IP_ANY</a></div><div class="ttdeci">@ S_CANNOT_CONNECT_TO_IP_ANY</div><div class="ttdoc">Cannot ask to connect to &quot;any&quot; IP address. Use specific IP address.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ab2c97d0fbc585d3726ec79c7802da891"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab2c97d0fbc585d3726ec79c7802da891">flow::net_flow::error::Code::S_CONN_RESET_BAD_PEER_BEHAVIOR</a></div><div class="ttdeci">@ S_CONN_RESET_BAD_PEER_BEHAVIOR</div><div class="ttdoc">Connection reset because of unexpected/illegal behavior by the other side.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ab835895723a7d71c964b84e0f0b78c3c"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab835895723a7d71c964b84e0f0b78c3c">flow::net_flow::error::Code::S_WAIT_USER_TIMEOUT</a></div><div class="ttdeci">@ S_WAIT_USER_TIMEOUT</div><div class="ttdoc">A blocking (sync_) or background-blocking (async_) operation timed out versus user-supplied time limi...</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ab92ec3b2b78d74acf0fda0786f601df5"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ab92ec3b2b78d74acf0fda0786f601df5">flow::net_flow::error::Code::S_WAIT_INTERRUPTED</a></div><div class="ttdeci">@ S_WAIT_INTERRUPTED</div><div class="ttdoc">A blocking (sync_) or background-blocking (async_) operation was interrupted, such as by a signal.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482abb79e941df00b67a8631a9361ee5a4d1"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482abb79e941df00b67a8631a9361ee5a4d1">flow::net_flow::error::Code::S_INVALID_SERVICE_PORT_NUMBER</a></div><div class="ttdeci">@ S_INVALID_SERVICE_PORT_NUMBER</div><div class="ttdoc">Flow port number is not in the valid service port number range.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ad7b8da59bb61205572fe985c29863e58"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ad7b8da59bb61205572fe985c29863e58">flow::net_flow::error::Code::S_STATIC_OPTION_CHANGED</a></div><div class="ttdeci">@ S_STATIC_OPTION_CHANGED</div><div class="ttdoc">When setting options, tried to set an unchangeable (static) option.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482adccb025a96014a74a1435481ec2b58ac"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482adccb025a96014a74a1435481ec2b58ac">flow::net_flow::error::Code::S_EVENT_SET_DOUBLE_WAIT_OR_POLL</a></div><div class="ttdeci">@ S_EVENT_SET_DOUBLE_WAIT_OR_POLL</div><div class="ttdoc">Attempted to wait on or poll an event set while already waiting on that event set.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ae643fd244bd1d6b483295cb9f356b0ae"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ae643fd244bd1d6b483295cb9f356b0ae">flow::net_flow::error::Code::S_EVENT_SET_CLOSED</a></div><div class="ttdeci">@ S_EVENT_SET_CLOSED</div><div class="ttdoc">Attempted operation on an event set, when that event set was closed.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482ae90ff1c87f2393dd6b14232b159f02b2"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482ae90ff1c87f2393dd6b14232b159f02b2">flow::net_flow::error::Code::S_INTERNAL_ERROR_PORT_COLLISION</a></div><div class="ttdeci">@ S_INTERNAL_ERROR_PORT_COLLISION</div><div class="ttdoc">Internal error: Ephemeral port double reservation allowed.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a18e13de77b119ea0f2be411490859482affac5d80b4e72f2e55bbbfadce2efd2e"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a18e13de77b119ea0f2be411490859482affac5d80b4e72f2e55bbbfadce2efd2e">flow::net_flow::error::Code::S_NODE_NOT_RUNNING</a></div><div class="ttdeci">@ S_NODE_NOT_RUNNING</div><div class="ttdoc">Node not running.</div></div>
<div class="ttc" id="anamespaceflow_1_1net__flow_1_1error_html_a6d35c37eb70a494bb27aa807c41de176"><div class="ttname"><a href="namespaceflow_1_1net__flow_1_1error.html#a6d35c37eb70a494bb27aa807c41de176">flow::net_flow::error::make_error_code</a></div><div class="ttdeci">Error_code make_error_code(Code err_code)</div><div class="ttdoc">Given a Code enum value, creates a lightweight flow::Error_code (a/k/a boost.system error_code) repre...</div><div class="ttdef"><b>Definition:</b> <a href="net__flow_2error_2error_8cpp_source.html#l00093">error.cpp:93</a></div></div>
<div class="ttc" id="anamespaceflow_html_a29eaaa9d0fac4ce87d8b969222dbed09"><div class="ttname"><a href="namespaceflow.html#a29eaaa9d0fac4ce87d8b969222dbed09">flow::Error_code</a></div><div class="ttdeci">boost::system::error_code Error_code</div><div class="ttdoc">Short-hand for a boost.system error code (which basically encapsulates an integer/enum error code and...</div><div class="ttdef"><b>Definition:</b> <a href="common_8hpp_source.html#l00508">common.hpp:508</a></div></div>
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